Free Traffic Legal Advice

My car was parked in Lewisham Hospital ANPR car park for 66 minutes on the 27th April. There are two options to pay for parking - by phone on arrival or at the ticket machine when leaving. At the time of leaving the ticket machine was out of order and the barrier was raised. It's a £40 PCN so not much, but in principle I feel that Wise Parking are holding people to ransom by leaving the ticket machine broken and sending out PCNs.